• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1674-1678
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• 2008

본 연구에서는 심장의 세포 변화에서부터 혈류 순환의 시스템 변화까지 일련의 과정을 시뮬레이션 할 수 있는 통합모델을 개발하였다. 본 통합 모델을 이용하여 대동맥의 탄성도 변화 따른 Pulse Wave Velocity를 추정하였으며 심근의 수축 Mechanics의 변화를 시뮬레이션 하였다. 심장은 단순한 구 형상으로 모델링 되었다. 특히 동맥순환의 특성인 Wave propagation 과 Wave deflection의 현상을 모델링하기 위해 기존 모델에서 사용된 동맥계 순환 모델을 수정하였다. 즉 기존의 동맥 모델을 1차원의 운동방정식과 연속방정식을 기반으로 하는 Distributed arterial model로 대체하였다. Distributed arterial model은 혈액의 점성에 의한 에너지 손실, 혈관의 점탄성 효과 그리고 분지 되는 혈관에서의 에너지 손실을 포함하는 정교한 동맥 순환 모델이다. 정교한 동맥계 순환 모델의 동맥 탄성도 값을 조절함으로써 탄성도 변화에 대한 PWV를 계산 할 수 있었다. 이러한 수치적 방법을 사용하여 노화에 따른 동맥벽 탄성도의 저하가 심근세포의 Cross-bridge 동역학에 미치는 영향을 시뮬레이션 하였다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.5
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• pp.444-450
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• 2008

The conventional studies of the aging effect on cardio-vascular system are mostly obtained from human experiences and can only provide local information. In this study, the effect of fatigue fracture of arterial wall on the blood pressure was investigated by hemodynamic analysis. The aging process was simulated with three stages. The pulse wave velocity increased with age. The systolic blood pressure increases consistently but diastolic blood pressure decreases with age. The simulated results show in good accordance with the clinical ones.

• Journal of Chest Surgery
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• v.26 no.11
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• pp.881-885
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• 1993

In the last few years there has been a resurgenceof interest in in-situ saphenous vein arterial bypass for lower extremity revascularization because of improved patency rates. we performed 1 in situ bypass oreration using the intraluminal valve-disruption tecnique. A 65-year-old female who had ztherosclerotic obstruction in the superficial and popliteal arteries underwent in situ saphenous vein arterial bypass. After harvesting of saphenous vein, we used LeMaitre retrograde valvulotome for valve-disruption technique. Completion of the arterrigraphy was performed to evaluate bothh the anastomoses. The two side brances were all ligated. In situ saphenous vein arterial bypass has become the procedure of choice for distal reconstruction in severely ischemic lower extremities because of improved long-term patency compared with reversed-saphenous vein bypass procedure.

• Korean Journal of Digital Imaging in Medicine
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• v.15 no.1
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• pp.27-31
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• 2013

Perfusion MR imaging is how to use exogenous and endogenous contrast agent. Exogenous perfusion MRI methods which are dynamic susceptibility contrast using $T2^*$ effect and dynamic contrast-enhanced using T1 weighted image after injection contrast media. An endogenous perfusion MRI method which is arterial spin labeling using arterial blood flow in body. In order to exam perfusion MRI in human, technical access are very important according to disease conditions. For instance, dynamic susceptibility contrast is used in patients with acute stroke because of short exam time, while dynamic susceptibility contrast or dynamic contrast enhancement provides the various perfusion information for patients with tumor, vascular stenosis. Arterial spin labeling is useful for children, women who are expected to be pregnant. In this regard, perfusion MR imaging is required to understanding, and the author would like to share information with clinical users

• Journal of Chest Surgery
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• v.1 no.1
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• pp.75-80
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• 1968

This is a case report of traumatic arterial injuries with false aneurysm & arterio-venous fistula treated surgically at National Medical Center. 3 cases were A-V fistula and 2 cases only false aneurysm. Physiological disturbance were produced by only arteriovenous fistula; In one case ulceration of mid. 1/3 tibia due to diminished arterial flow and in 2 cases left ventricular hypertrophy, in which cases Bramhan`s sign were positive. Removing out the fistulous lesions and aneurysm, all of the arterial continuities has been reconstructed by means of end to end anastomosis, Dacron graft and vein graft, veins were managed by ligations of both ends in two cases and end to end anostomosis in one case. Immediate post operative results were good, and two cases were followed for 10 months.

• The Journal of Internal Korean Medicine
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• v.18 no.2
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• pp.160-166
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• 1997

To evaluate the effect of acupuncture on the hypertension, the study was done by acupuncture on bilateral Inyong(ST9) with rats which are normal and acutely increased hypertensive. The results are as follows: 1. Under the normal condition, the acupuncture on bilateral Inyong caused a quick drop of mean arterial pressure(MAP), but heart rate(HR) was not changed significantly. 2. To increase the blood pressure, acutely epinephrine was administered and it caused a increase in both MAP and HR. With acupuncture, the MAP was decreased while HR did not show a significant change. In conclusion, the acupuncture was somewhat effective in lowering the mean arterial pressure in the rat.

• Molecules and Cells
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• v.37 no.3
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• pp.196-201
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• 2014

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by the vascular remodeling of the pulmonary arterioles, including formation of plexiform and concentric lesions comprised of proliferative vascular cells. Clinically, PAH leads to increased pulmonary arterial pressure and subsequent right ventricular failure. Existing therapies have improved the outcome but mortality still remains exceedingly high. There is emerging evidence that the seven-transmembrane G-protein coupled receptor APJ and its cognate endogenous ligand apelin are important in the maintenance of pulmonary vascular homeostasis through the targeting of critical mediators, such as Kr$\ddot{u}$ppel-like factor 2 (KLF2), endothelial nitric oxide synthase (eNOS), and microRNAs (miRNAs). Disruption of this pathway plays a major part in the pathogenesis of PAH. Given its role in the maintenance of pulmonary vascular homeostasis, the apelin-APJ pathway is a potential target for PAH therapy. This review highlights the current state in the understanding of the apelin-APJ axis related to PAH and discusses the therapeutic potential of this signaling pathway as a novel paradigm of PAH therapy.

• Journal of Chest Surgery
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• v.51 no.6
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• pp.395-398
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• 2018

Neo-aortic insufficiency associated with root enlargement following an arterial switch operation is a serious late complication. To achieve successful surgical correction of this condition, multiple factors should be considered, including the individual patient's anatomy, the challenging nature of the redo procedure, and the patient's young age. However, limited publications have described the use of valve-sparing techniques for the treatment of neo-aortic insufficiency associated with root enlargement following an arterial switch operation. Herein, we report our recent experience of a valve-sparing aortic root procedure with ascending aorta and hemiarch replacement despite the presence of a discrepancy in leaflet size and nearby severe adhesions.

• Journal of Korean Port Research
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• v.8 no.2
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• pp.79-105
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• 1994

Today travel demand in the City of Pusan is increasing with the wide scope of activity and the better living circumstances as a big city with a population of about 4 million. Also, the transportation problem of Pusan city becomes one of the severest urban problems with travel demand increasing in spite of the continuous expansion of the transportation facilities. The purpose in this study is to find the travel characteristics on the arterial under the study, construct the optimal Transportation System Management(TSM) which could increase the travel capacity of the arterial based upon the optimal travel systems constructed. Thus, it was concluded that more emphasis should be of the automobiles into the Downtown areas, increase the travel capacity of the arterial through Mass Transportation System(MTS) including the HOV lanes or the Bus Exclusive Lanes instead.

• 순환기질환의공학회:학술대회논문집
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• 2006.10a
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• pp.27-29
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• 2006